@misc{indiciae423240c8a703,
  title = {Spontaneous preterm birth: a case-control study.},
  author = {I de Haas and B L Harlow and D W Cramer and F D Frigoletto},
  year = {1991},
  url = {https://pubmed.ncbi.nlm.nih.gov/1957848/},
  note = {Source identifier: 1957848}
}